IB/qib: Add cache line awareness to qib_qp and qib_devdata structures

This patch reorganizes the QP and devdata files to be more cache line aware.

qib_qp fields in particular are split into read-mostly, send, and receive fields.

qib_devdata fields are split into read-mostly and read/write fields

Testing has show that bidirectional tests improve by as much as 100%
with this patch.

Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
diff --git a/drivers/infiniband/hw/qib/qib_ud.c b/drivers/infiniband/hw/qib/qib_ud.c
index 828609f..a468bf2 100644
--- a/drivers/infiniband/hw/qib/qib_ud.c
+++ b/drivers/infiniband/hw/qib/qib_ud.c
@@ -321,11 +321,11 @@
 
 	if (ah_attr->ah_flags & IB_AH_GRH) {
 		/* Header size in 32-bit words. */
-		qp->s_hdrwords += qib_make_grh(ibp, &qp->s_hdr.u.l.grh,
+		qp->s_hdrwords += qib_make_grh(ibp, &qp->s_hdr->u.l.grh,
 					       &ah_attr->grh,
 					       qp->s_hdrwords, nwords);
 		lrh0 = QIB_LRH_GRH;
-		ohdr = &qp->s_hdr.u.l.oth;
+		ohdr = &qp->s_hdr->u.l.oth;
 		/*
 		 * Don't worry about sending to locally attached multicast
 		 * QPs.  It is unspecified by the spec. what happens.
@@ -333,7 +333,7 @@
 	} else {
 		/* Header size in 32-bit words. */
 		lrh0 = QIB_LRH_BTH;
-		ohdr = &qp->s_hdr.u.oth;
+		ohdr = &qp->s_hdr->u.oth;
 	}
 	if (wqe->wr.opcode == IB_WR_SEND_WITH_IMM) {
 		qp->s_hdrwords++;
@@ -346,15 +346,15 @@
 		lrh0 |= 0xF000; /* Set VL (see ch. 13.5.3.1) */
 	else
 		lrh0 |= ibp->sl_to_vl[ah_attr->sl] << 12;
-	qp->s_hdr.lrh[0] = cpu_to_be16(lrh0);
-	qp->s_hdr.lrh[1] = cpu_to_be16(ah_attr->dlid);  /* DEST LID */
-	qp->s_hdr.lrh[2] = cpu_to_be16(qp->s_hdrwords + nwords + SIZE_OF_CRC);
+	qp->s_hdr->lrh[0] = cpu_to_be16(lrh0);
+	qp->s_hdr->lrh[1] = cpu_to_be16(ah_attr->dlid);  /* DEST LID */
+	qp->s_hdr->lrh[2] = cpu_to_be16(qp->s_hdrwords + nwords + SIZE_OF_CRC);
 	lid = ppd->lid;
 	if (lid) {
 		lid |= ah_attr->src_path_bits & ((1 << ppd->lmc) - 1);
-		qp->s_hdr.lrh[3] = cpu_to_be16(lid);
+		qp->s_hdr->lrh[3] = cpu_to_be16(lid);
 	} else
-		qp->s_hdr.lrh[3] = IB_LID_PERMISSIVE;
+		qp->s_hdr->lrh[3] = IB_LID_PERMISSIVE;
 	if (wqe->wr.send_flags & IB_SEND_SOLICITED)
 		bth0 |= IB_BTH_SOLICITED;
 	bth0 |= extra_bytes << 20;